xref: /dragonfly/lib/libc/rpc/svc.c (revision 2e3ed54d) 
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  *
29  * @(#)svc.c 1.44 88/02/08 Copyr 1984 Sun Micro
30  * @(#)svc.c	2.4 88/08/11 4.0 RPCSRC
31  * $FreeBSD: src/lib/libc/rpc/svc.c,v 1.14.2.1 2001/03/05 10:50:36 obrien Exp $
32  * $DragonFly: src/lib/libc/rpc/svc.c,v 1.4 2005/11/13 12:27:04 swildner Exp $
33  */
34 
35 /*
36  * svc.c, Server-side remote procedure call interface.
37  *
38  * There are two sets of procedures here.  The xprt routines are
39  * for handling transport handles.  The svc routines handle the
40  * list of service routines.
41  *
42  * Copyright (C) 1984, Sun Microsystems, Inc.
43  */
44 
45 #include <string.h>
46 #include <stdlib.h>
47 #include <rpc/rpc.h>
48 #include <rpc/pmap_clnt.h>
49 
50 static SVCXPRT **xports;
51 static int xportssize;
52 
53 #define NULL_SVC ((struct svc_callout *)0)
54 #define	RQCRED_SIZE	400		/* this size is excessive */
55 
56 #define max(a, b) (a > b ? a : b)
57 
58 /*
59  * The services list
60  * Each entry represents a set of procedures (an rpc program).
61  * The dispatch routine takes request structs and runs the
62  * apropriate procedure.
63  */
64 static struct svc_callout {
65 	struct svc_callout *sc_next;
66 	u_long		    sc_prog;
67 	u_long		    sc_vers;
68 	void		    (*sc_dispatch)();
69 } *svc_head;
70 
71 static struct svc_callout *svc_find();
72 
73 int __svc_fdsetsize = 0;
74 fd_set *__svc_fdset = NULL;
75 
76 /* ***************  SVCXPRT related stuff **************** */
77 
78 /*
79  * Activate a transport handle.
80  */
81 void
82 xprt_register(SVCXPRT *xprt)
83 {
84 	int sock = xprt->xp_sock;
85 
86 	if (sock + 1 > __svc_fdsetsize) {
87 		int bytes = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
88 		fd_set *fds;
89 
90 		fds = (fd_set *)malloc(bytes);
91 		memset(fds, 0, bytes);
92 		if (__svc_fdset) {
93 			memcpy(fds, __svc_fdset, howmany(__svc_fdsetsize,
94 				NFDBITS) * sizeof(fd_mask));
95 			free(__svc_fdset);
96 		}
97 		__svc_fdset = fds;
98 		__svc_fdsetsize = howmany(sock+1, NFDBITS) * NFDBITS;
99 	}
100 
101 	if (sock < FD_SETSIZE)
102 		FD_SET(sock, &svc_fdset);
103 	FD_SET(sock, __svc_fdset);
104 
105 	if (xports == NULL || sock + 1 > xportssize) {
106 		SVCXPRT **xp;
107 		int size = FD_SETSIZE;
108 
109 		if (sock + 1 > size)
110 			size = sock + 1;
111 		xp = (SVCXPRT **)mem_alloc(size * sizeof(SVCXPRT *));
112 		memset(xp, 0, size * sizeof(SVCXPRT *));
113 		if (xports) {
114 			memcpy(xp, xports, xportssize * sizeof(SVCXPRT *));
115 			free(xports);
116 		}
117 		xportssize = size;
118 		xports = xp;
119 	}
120 	xports[sock] = xprt;
121 	svc_maxfd = max(svc_maxfd, sock);
122 }
123 
124 /*
125  * De-activate a transport handle.
126  */
127 void
128 xprt_unregister(SVCXPRT *xprt)
129 {
130 	int sock = xprt->xp_sock;
131 
132 	if (xports[sock] == xprt) {
133 		xports[sock] = (SVCXPRT *)0;
134 		if (sock < FD_SETSIZE)
135 			FD_CLR(sock, &svc_fdset);
136 		FD_CLR(sock, __svc_fdset);
137 		if (sock == svc_maxfd) {
138 			for (svc_maxfd--; svc_maxfd >= 0; svc_maxfd--)
139 				if (xports[svc_maxfd])
140 					break;
141 		}
142 		/*
143 		 * XXX could use svc_maxfd as a hint to
144 		 * decrease the size of __svc_fdset
145 		 */
146 	}
147 }
148 
149 
150 /* ********************** CALLOUT list related stuff ************* */
151 
152 /*
153  * Add a service program to the callout list.
154  * The dispatch routine will be called when a rpc request for this
155  * program number comes in.
156  */
157 bool_t
158 svc_register(SVCXPRT *xprt, u_long prog, u_long vers, void (*dispatch)(),
159 	     int protocol)
160 {
161 	struct svc_callout *prev;
162 	struct svc_callout *s;
163 
164 	if ((s = svc_find(prog, vers, &prev)) != NULL_SVC) {
165 		if (s->sc_dispatch == dispatch)
166 			goto pmap_it;  /* he is registering another xptr */
167 		return (FALSE);
168 	}
169 	s = (struct svc_callout *)mem_alloc(sizeof(struct svc_callout));
170 	if (s == (struct svc_callout *)0) {
171 		return (FALSE);
172 	}
173 	s->sc_prog = prog;
174 	s->sc_vers = vers;
175 	s->sc_dispatch = dispatch;
176 	s->sc_next = svc_head;
177 	svc_head = s;
178 pmap_it:
179 	/* now register the information with the local binder service */
180 	if (protocol) {
181 		return (pmap_set(prog, vers, protocol, xprt->xp_port));
182 	}
183 	return (TRUE);
184 }
185 
186 /*
187  * Remove a service program from the callout list.
188  */
189 void
190 svc_unregister(u_long prog, u_long vers)
191 {
192 	struct svc_callout *prev;
193 	struct svc_callout *s;
194 
195 	if ((s = svc_find(prog, vers, &prev)) == NULL_SVC)
196 		return;
197 	if (prev == NULL_SVC) {
198 		svc_head = s->sc_next;
199 	} else {
200 		prev->sc_next = s->sc_next;
201 	}
202 	s->sc_next = NULL_SVC;
203 	mem_free((char *) s, (u_int) sizeof(struct svc_callout));
204 	/* now unregister the information with the local binder service */
205 	pmap_unset(prog, vers);
206 }
207 
208 /*
209  * Search the callout list for a program number, return the callout
210  * struct.
211  */
212 static struct svc_callout *
213 svc_find(u_long prog, u_long vers, struct svc_callout **prev)
214 {
215 	struct svc_callout *s, *p;
216 
217 	p = NULL_SVC;
218 	for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
219 		if ((s->sc_prog == prog) && (s->sc_vers == vers))
220 			goto done;
221 		p = s;
222 	}
223 done:
224 	*prev = p;
225 	return (s);
226 }
227 
228 /* ******************* REPLY GENERATION ROUTINES  ************ */
229 
230 /*
231  * Send a reply to an rpc request
232  */
233 bool_t
234 svc_sendreply(SVCXPRT *xprt, xdrproc_t xdr_results, caddr_t xdr_location)
235 {
236 	struct rpc_msg rply;
237 
238 	rply.rm_direction = REPLY;
239 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
240 	rply.acpted_rply.ar_verf = xprt->xp_verf;
241 	rply.acpted_rply.ar_stat = SUCCESS;
242 	rply.acpted_rply.ar_results.where = xdr_location;
243 	rply.acpted_rply.ar_results.proc = xdr_results;
244 	return (SVC_REPLY(xprt, &rply));
245 }
246 
247 /*
248  * No procedure error reply
249  */
250 void
251 svcerr_noproc(SVCXPRT *xprt)
252 {
253 	struct rpc_msg rply;
254 
255 	rply.rm_direction = REPLY;
256 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
257 	rply.acpted_rply.ar_verf = xprt->xp_verf;
258 	rply.acpted_rply.ar_stat = PROC_UNAVAIL;
259 	SVC_REPLY(xprt, &rply);
260 }
261 
262 /*
263  * Can't decode args error reply
264  */
265 void
266 svcerr_decode(SVCXPRT *xprt)
267 {
268 	struct rpc_msg rply;
269 
270 	rply.rm_direction = REPLY;
271 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
272 	rply.acpted_rply.ar_verf = xprt->xp_verf;
273 	rply.acpted_rply.ar_stat = GARBAGE_ARGS;
274 	SVC_REPLY(xprt, &rply);
275 }
276 
277 /*
278  * Some system error
279  */
280 void
281 svcerr_systemerr(SVCXPRT *xprt)
282 {
283 	struct rpc_msg rply;
284 
285 	rply.rm_direction = REPLY;
286 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
287 	rply.acpted_rply.ar_verf = xprt->xp_verf;
288 	rply.acpted_rply.ar_stat = SYSTEM_ERR;
289 	SVC_REPLY(xprt, &rply);
290 }
291 
292 /*
293  * Authentication error reply
294  */
295 void
296 svcerr_auth(SVCXPRT *xprt, enum auth_stat why)
297 {
298 	struct rpc_msg rply;
299 
300 	rply.rm_direction = REPLY;
301 	rply.rm_reply.rp_stat = MSG_DENIED;
302 	rply.rjcted_rply.rj_stat = AUTH_ERROR;
303 	rply.rjcted_rply.rj_why = why;
304 	SVC_REPLY(xprt, &rply);
305 }
306 
307 /*
308  * Auth too weak error reply
309  */
310 void
311 svcerr_weakauth(SVCXPRT *xprt)
312 {
313 
314 	svcerr_auth(xprt, AUTH_TOOWEAK);
315 }
316 
317 /*
318  * Program unavailable error reply
319  */
320 void
321 svcerr_noprog(SVCXPRT *xprt)
322 {
323 	struct rpc_msg rply;
324 
325 	rply.rm_direction = REPLY;
326 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
327 	rply.acpted_rply.ar_verf = xprt->xp_verf;
328 	rply.acpted_rply.ar_stat = PROG_UNAVAIL;
329 	SVC_REPLY(xprt, &rply);
330 }
331 
332 /*
333  * Program version mismatch error reply
334  */
335 void
336 svcerr_progvers(SVCXPRT *xprt, u_long low_vers, u_long high_vers)
337 {
338 	struct rpc_msg rply;
339 
340 	rply.rm_direction = REPLY;
341 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
342 	rply.acpted_rply.ar_verf = xprt->xp_verf;
343 	rply.acpted_rply.ar_stat = PROG_MISMATCH;
344 	rply.acpted_rply.ar_vers.low = low_vers;
345 	rply.acpted_rply.ar_vers.high = high_vers;
346 	SVC_REPLY(xprt, &rply);
347 }
348 
349 /* ******************* SERVER INPUT STUFF ******************* */
350 
351 /*
352  * Get server side input from some transport.
353  *
354  * Statement of authentication parameters management:
355  * This function owns and manages all authentication parameters, specifically
356  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
357  * the "cooked" credentials (rqst->rq_clntcred).
358  * However, this function does not know the structure of the cooked
359  * credentials, so it make the following assumptions:
360  *   a) the structure is contiguous (no pointers), and
361  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
362  * In all events, all three parameters are freed upon exit from this routine.
363  * The storage is trivially management on the call stack in user land, but
364  * is mallocated in kernel land.
365  */
366 
367 void
368 svc_getreq(int rdfds)
369 {
370 	fd_set readfds;
371 
372 	FD_ZERO(&readfds);
373 	readfds.fds_bits[0] = rdfds;
374 	svc_getreqset(&readfds);
375 }
376 
377 void
378 svc_getreqset(fd_set *readfds)
379 {
380 	svc_getreqset2(readfds, FD_SETSIZE);
381 }
382 
383 void
384 svc_getreqset2(fd_set *readfds, int width)
385 {
386 	enum xprt_stat stat;
387 	struct rpc_msg msg;
388 	int prog_found;
389 	u_long low_vers;
390 	u_long high_vers;
391 	struct svc_req r;
392 	SVCXPRT *xprt;
393 	int bit;
394 	int sock;
395 	fd_mask mask, *maskp;
396 	char cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];
397 	msg.rm_call.cb_cred.oa_base = cred_area;
398 	msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
399 	r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);
400 
401 
402 	maskp = readfds->fds_bits;
403 	for (sock = 0; sock < width; sock += NFDBITS) {
404 	    for (mask = *maskp++; (bit = ffs(mask)); mask ^= (1 << (bit - 1))) {
405 		/* sock has input waiting */
406 		xprt = xports[sock + bit - 1];
407 		if (xprt == NULL)
408 			/* But do we control sock? */
409 			continue;
410 		/* now receive msgs from xprtprt (support batch calls) */
411 		do {
412 			if (SVC_RECV(xprt, &msg)) {
413 
414 				/* now find the exported program and call it */
415 				struct svc_callout *s;
416 				enum auth_stat why;
417 
418 				r.rq_xprt = xprt;
419 				r.rq_prog = msg.rm_call.cb_prog;
420 				r.rq_vers = msg.rm_call.cb_vers;
421 				r.rq_proc = msg.rm_call.cb_proc;
422 				r.rq_cred = msg.rm_call.cb_cred;
423 				/* first authenticate the message */
424 				if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
425 					svcerr_auth(xprt, why);
426 					goto call_done;
427 				}
428 				/* now match message with a registered service*/
429 				prog_found = FALSE;
430 				low_vers = (u_long) - 1;
431 				high_vers = 0;
432 				for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
433 					if (s->sc_prog == r.rq_prog) {
434 						if (s->sc_vers == r.rq_vers) {
435 							(*s->sc_dispatch)(&r, xprt);
436 							goto call_done;
437 						}  /* found correct version */
438 						prog_found = TRUE;
439 						if (s->sc_vers < low_vers)
440 							low_vers = s->sc_vers;
441 						if (s->sc_vers > high_vers)
442 							high_vers = s->sc_vers;
443 					}   /* found correct program */
444 				}
445 				/*
446 				 * if we got here, the program or version
447 				 * is not served ...
448 				 */
449 				if (prog_found)
450 					svcerr_progvers(xprt,
451 					low_vers, high_vers);
452 				else
453 					 svcerr_noprog(xprt);
454 				/* Fall through to ... */
455 			}
456 		call_done:
457 			if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
458 				SVC_DESTROY(xprt);
459 				break;
460 			}
461 		} while (stat == XPRT_MOREREQS);
462 	    }
463 	}
464 }
465